The present invention relates to a theft preventive apparatus and a radio wave receiving signaling device, and more particularly to a theft preventive apparatus apparatus including a box to be attached to an object of theft prevention, preliminary act detecting means provided in the box for detecting a preliminary theft act, alarm output means disposed inside the box for outputting alarm information based on detection information of the preliminary act detecting means, retaining means for retaining the alarm output means at an operative state, alarm release means for stopping an operation of the alarm output means, an insertion hole being defined in an outer periphery of the box extending into the box, the alarm release means being operable to an alarm releasing state by a bar-like releasing tool inserted into the insertion hole. The invention relates also to a radio wave receiving signaling device used with the theft preventive apparatus.
Such theft preventive apparatus is used as being attached to an object of theft prevention such as a commodity displayed at a shop. When a preliminary stealing act is committed, i.e. when the box of the theft preventive apparatus is unlawfully removed from the object of theft prevention or when the object of theft prevention together with the box of the theft preventive apparatus being attached thereto is unlawfully taken out of the shop, this is detected and the alarm output means outputs alarm information, such that a shop attendant or the like is notified of the commitment of such preliminary stealing act as described above, whereby loss due to theft may be prevented.
On the other hand, when the object of theft prevention is lawfully provided to its purchaser, it is necessary to remove the theft preventive apparatus from the object of theft prevention. And, in this removing operation, the alarm output means needs to be rendered inoperative.
For rendering the alarm output means inoperative, the alarm release means is provided. By inserting the bar-like releasing tool into the insertion hole defined in the box of the theft preventive apparatus, the alarm releasing means is operated into the alarm releasing state to render the alarm output means inoperative. Then, the theft preventive apparatus may be removed from the object of theft prevention.
Further, when the theft preventive apparatus is used as being attached to the object of theft prevention, based on an activation instruction, the retaining means retains the alarm output means at the operative state. Namely, the alarm output means is maintained at the inoperative state before use to save electric power consumption, and the alarm output means is reliably retained at the operative state under the in-use condition.
As the retaining means, the convention has provided the followings.
For instance, as disclosed in a Japanese patent application Hei. 5-215886 by the present applicant, there is provided a switch for allowing or inhibiting electric power supply to the alarm output means. This switch is turned ON by means of an operated tool which slides in association with attachment of an attachment member to the object of theft prevention. Also, in association with the sliding movement, a retaining element comprised of a spring wire element automatically comes into engagement of a retaining piece of the operated tool, thereby to retain the operated tool at the switched-on position against the urging force of the spring. This retaining mechanism constitutes the retaining means described above.
However, with the conventional art described above, the alarm output means is retained at the operative state by means of the retaining mechanism described above. Then, with application of vibration for instance, the retained state may be released. Or, after the retaining action and the releasing action are repeated for a number of times, there occurs such inconvenience as frictional wear which renders the retaining mechanism unreliable.
Then, in order to improve retaining function, it is conceivable to improve the construction of the retaining mechanism so that the mechanism may provide more reliable retaining function. However, such improvement renders the construction complicated and enlarges the entire apparatus.
Moreover, with the above-described conventional art, when a bar-like fake operating tool similar to the releasing tool is unlawfully inserted into the insertion hole for the release operation, the retaining state of the retaining mechanism may be relatively easily released to render the alarm output means inoperative. Thus, in this respect too, there has been room for improvement.
The present invention has been made in consideration to the above-described state of the art. Its first object is to provide a theft preventive apparatus which can reliably maintain the alarm output means under the operative state without inviting enlargement of the apparatus.
A further object is to inhibit the alarm output means from being readily rendered into the inoperative state unlawfully by e.g. a fake operating tool other than the authorized releasing tool.
A still further object is to provide a theft preventive apparatus which is easy to handle and practical such as being resistant against erroneous operation.
A still further object is to provide a radio wave receiving signaling device to be used with the theft preventive apparatus described above.